Expansion Joint Bolt Circle Diameter 3 1/8 in Bolt Hole Size 1/2 In.-13 Bolt Hole Threading Threaded Burst Pressure 853 psi Compression Distance 5/8 in Connection Type Flanged Expansion Distance 3/8 in Expansion Joint Type Single Bulb Features Absorbs Pipe Movement and Stress Flange Diameter 4 1/4 in Flange Material Steel Flange Material Finish Zinc-Plated For Fluid Type Air Water Joint Material EPDM Joint Material Finish Not Applicable Joint Material Grade Not Applicable